Who is responsible for creating documentation that explains how the software operates?

The responsibility for creating documentation that explains how the software operates is typically assigned to the developer. Developers have an in-depth understanding of the code, algorithms, and system architecture, which enables them to provide detailed explanations and insights into how the software functions. They create technical documentation, such as code comments, API documentation, and user manuals, to help other developers, testers, or end-users understand the software.

While designers focus on the user interface and user experience, their documentation primarily revolves around design principles and specifications rather than the operational aspects of the software itself. Testers are primarily concerned with validating and verifying the software to ensure it meets requirements and expected behaviors, rather than documenting how it operates. Project managers oversee the development process but do not usually create technical documentation about the software.